Thirteen University of Iowa Football Players Hospitalized

"It's treated early on by flushing the system with lots of fluid, and then people will alkalinize the urine and make it basic so deposits don't hurt the kidney as much," said Teperman.

While heavy exercise and trauma can lead to the condition, some medications can also cause it in a small number of people.

"High doses of drugs like statins are associated with this problem, especially among people with diabetes, or people who are organ transplant patients that take medications that interact in a way that increse the risks of getting rhabdomyolysis," said Dr. Bryan Becker, a spokesperson for the National Kidney Foundation.

Condition Can Be Mistaken For Other Illnesses

Experts say the condition is neither common nor uncommon. They see cases of it every year, but more often in the summer because lots of strenuous exercise in the heat.

Symptoms include extremely sore muscles and tea-colored urine. It can sometimes be mistaken for other illnesses that cause muscle aches, such as the flu. A blood test is generally the only way to distinguish rhabdomyolysis from other conditions.

Specialists strongly recommend getting enough hydration before, during and after workouts. Athletes should also take adequate breaks during training. They should also eat certain types of foods.

"A peanut butter and jelly sandwich, [or] a regular granola bar with a little bit of milk or cereal and milk, just before exercise. Or even just a handful of peanuts or pretzels., that would be fine," said Mone. "And after a workout, again, within 30 minutes of that workout you should refuel appropriately with something like chocolate milk or a balanced meal that's going to have carbohydrate, protein, and fat."

Federici said workouts have resumed for the other players, but he said he's not sure if the training regimen will change.

The Iowa Board of Regents, the governing body for five public education institutions including the University of Iowa, requested a 90-day investigation what caused the illnesses.

"The primary aim of this analysis will be to identify, to the extent possible, the root causes of this
incident in order to create and implement effective preventative measures to ensure this does not
happen in the future," the board said in a statement.